Pneumatic door operating mechanism



Nov. 8, 1932. c. NORTON PNEUMATIC DOOR OPERATING MECHANISM 4 Sheets-Sheet 1 Original Filed July 7, 1923 mm n m dA M Q m QYMW Nov. 8, 1932.

C. NORTON PNEUMATIC DOOR OPERATING MECHANISM Original Filed July 7, 1923 4 Sheets-Sheet 2 INVENTOR C //'ffora Norfon LMW TTORNEYS Nov. 8, 1932. c, NORTON 1,887,212

PNEUMATIC DOOR OPERATING MECHANISM Original Filed July 7, 1925 4 Sheets-Sheet 3 Pram Q'y/Mder INVENTOR WMMQQ w,

Nov. 8, 1932. c. NORTON PNEUMATIC DOOR OPERATING MECHANISM Original Filed July 7, 1923 4 Sheets-Sheet 4 L%\ \XX g'POS/f/Ofi IVQ/ 3L/ 20 Pas/W0 INVENTOR sad Patented Nov. 8, 1932 UNITED STATES CLIFFORD NORTON, OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGN- PATENT OFFICE MENTS, TO OTIS ELEVATOR COMPANY, A CORPORATION OF NEW. JERSEY PNEUMATIG DOOR OPERATING'NIECHANISM Original application filed July 7,1923,

My invention relates to door operating mechanism particularly designed for application to the doors of elevators or elevator wells although it is readily adaptable to use for other doors whereinit is desired to secure a rapid movement both in closing and opening by power.

The object of my present invention is, generally stated, to secure a quick or rapid movement of the door and at the same time provide for a suitable cushioning or checking of the movement near the end of the excursion of the doorin reaching the closed or open position.

In apparatus constructed according to my invention I provide means for opening the door by the application of pneumatic power transferred from a piston to the door by any suitable means and I provide for the closing movement of the door by power stored in a spring during the opening of the door by the pneumatically actuated piston. The spring so employed is preferably one. which is constructed to have a graduated action either by the form of the spring itself or by the employment of two springs, as described in patent of Norton No. 1,124,941, dated January 12, 19-15, so that, while the door is caused to move rapidly under the action of the stored power at the beginning of its movement, its

final movement is produced by weaker spring 1 action.

Incombination with the pneumatically actuated piston for opening the door and the power storing spring used in connection therewith and serving to close the door, I employ a pair of liquid dashpots, as more particularly hereinafter described, whereby the pneumatic power applied for the opening movement and storage of power in the spring may be checked near the end of the opening movement by one of the dashpots to prevent sudden rebound or shock and whereby, in the closing movement under the action of the spring,the door may be cushioned or checked by the action of the other dashpot.

In carrying out my invention I regulate or adjust the dashpot actions in such manner that the checking effect applied during the opening movement when the springis com- Serial No. 650,044. Divided and this application filed March 12, 1928. Serial NO. 261,010.

pressed, will permit the door to move at much greater speed than'it will move under the action of the spring in the closing movement. By thus speeding up the opening movement I am enabled to greatly lessen the time consumed in the complete door opening and closing actions, thereby speeding up the service and lessening the headway. I also prefer to provide for each dashpot two or more regulable bypasses.actingconsecutively and each regulable independently of the other.

The control of the pneumatic power for opening the door and storing power and the control of'the action of the spring for the closing movement is attained by the use of a suitable pneumatic controlling valve as hereinafter described, by which pneumatic pressure is applied to the piston to effect the opening, the door being retained against the influence of the spring by the pressure, and by which, in the opposite position, an exhaust is opened and pressure cut ofi" to allow the spring to act, thus returningthe piston to the normal position and at the same time closingthe door. I

The invention'as thus outlined will be described in connection with the accompanying drawings and then specified more particularly in the claims. I

In the accompanying drawings:

Fig. 1 isa general side elevation partly sectional, of an apparatus embodying my invention, the door'being shown in closed position.

7 Fig. 2 shows the same apparatus with the door open. v

Fig. 3 illustrates the arrangement of parts of the pneumatic valve in a diagrammatic way and shows the position of the valve by which pressure is applied to open the door and store power in the spring.

Fig. 4 illustrates the corresponding or reverse position wherein the pressure is cut oil and the spring is allowed to act.

Fig. 5 is a horizontal section through the valve and valve casting.

Fig. 6 is an I enlarged vertical section through the two dashpots showing their pis tons both in their uppermost position.

Fig. 7 is a cross-section through one of the dashpot cylinders.

1 indicates an elevator or other door shown in this particular instance as a sliding shaft door, it being understood that there is one such door for each landing served by the elevator car 30, and as usual in the art, capable of sliding across the door opening. The operating mechanism for applying power to the door may be a lever or system of levers or any other desired mechanical devices operatively connecting the pneumatically actuated piston therewith. An operating mechanism suitable for use in carrying out my invention is shown for purposes of illustration as consisting of toggle arm or levers 2, 2 pivoted together, as at 3. One of said arms is pivoted to the door and the other is pivoted on a fixed bracket or abutment 1. When the door is closed the toggle is straight and the door is locked against movement to open it but by lifting the arm 2', by power applied to the same near its pivot, the toggle is broken and the door moved back to position indicated in Fig. 2. Power applied: to lower the lever 2 straightens the toggle and moves the door to closed position.

5 indicates a cylinder containing the pneu matically actuated piston 5' adapted to be lifted through pneumatic power applied through operation of a suitable valve 6. Between the piston 5 and the head of the cylinder a power storing spring is applied, as indicated, which is compressed as the piston moves up under the pneumatic power and serves to store power for closing the door. The power of this spring applied in closing the door may be adjusted by means of the adjustable confining cap applied thereto at the open end of the cylinder in which the piston works. The piston rod 7 is provided with cross-head 8 carrying a guide rod 9 which works in guide brackets, as shown, secured to a suitable fixed support as for in stance a wall or studding. Extending from the cross-head 8 upwardly is a link 10 pivoted to the cross-head and pivotally connected with the arm or lever 2 by the ear or arm 10. Also attached pivotally to thecrosshead is a link 11 extending downwardly and pivotally connected with a lever 12. Said lever, at opposite sides of its fulcrum, is connected to the pistons of the two liquid dashpots 13, 13 so that, as the crosshead rises in opening the door, the piston of dashpot 13 will be depressed and that of 13' raised, while in the opposite movement or closing movement of the door under the action of the spring and lowering of the cross-head there by, the piston of dashpot 13 will be depressed and that of 13 will rise. Said dashpot cylinders are preferably mounted at their closed or lower ends pivotally on the bracketl i, as indicated, to allow them to swing and accommodate themselves tothe movement of the attached ends of the pistons in the arcs of circles where they are joined to the lever 12.

The controller valve 6 controlling the application and relief of the pneumatic pres sure to produce the two movements of the door may be constructed as shown in Figs. 3 and 1 wherein 15 indicates the valve casting for a valve of the rotatable disk type. The stem of the valve, indicated at 16, is preferably disposed horizontally and carries the disk valve 17. The body of the valve casting is provided, if desired, with a boss 15 threaded for attachment to the lower end of the pneumatic cylinder 5, as shown, thereby affording a support for the valve. The casting is bored horizontally with suitable ports to which are attached pipes or connections from the air supply, to the cylinder, and to theexhaust as indicated by the legends on Figs. 3 and 1, while the disk itself is provided with openings from the face thereof exposed to pressure in the valve chamber 18 to the face which rides upon the face of the casting into which the bored ports extend. These openings are of substantially the form and dimensions indicated by the full lines in the figures while the face engaging the face of the casting is provided with a depression or port adapted to open and close the exhaust and of a form indicated by dotted lines.

It will be understood that the toggle mechanism 2, 2 forms a complete closure moving mechanism operable by the pneumatic power means and spring means disclosed or, if for any reason it becomes necessary or desirable that the power means should not be used, then the door may be moved manually by means of the toggle links since the exhaust is maintained in an opened or inoperative condition at all times except when the door is being opened by power.

In the operation of the apparatus the valve reciprocates between the positions indicated in Figs. 8 and 4. In the position Fig. 3, obviously, air is admitted under pressure to the cylinder and will. be confined therein owing to the closing of the exhaust until the valve is turned to position indicated in Fig. 4;, in which position the air supply will be cut off from the cylinder and the exhaust will be opened.

In the first position the pneumatic power will be applied to the piston of the cylinder 5, the door will be opened and at the same time power will be stored in the spring within said cylinder. When the valve is turned to the position shown in Fig. 4, the air will be permitted to exhaust from the cylinder and the spring will act, throwing the piston down, and the door will be closed. In the one movement, to wit: the opening movement, the dashpot cylinder 13 acts, while in the reverse movement or closing movement the dashpot 13 acts through depression of its piston. The lifting movements of the pistons of the Sol dashpots are not effectively opposed owing tothe presence of the relief valves in the pistons,'as shown, which open automatically and allow the liquid to circulate freely from one side of the piston to the other. To aid in free-. dom of movement of the piston in 13 during the major portion of the opening movement of the door, the cylinder therefor may be counterbored at a number of points around the piston as indicated in the sectional view Fig. 6. Said counterbores allow the liquid to pass freely from one side ofthe piston to the other on the down movement until the greater checking action is applied by the reg ulated bypass or bypasses near the end of the opening movement of the door.

I11 practice I prefer to provide for said dashpot 13 two or more bypasses 19, 19 regulable independently of one another by means of the usual regulating valve like a needle valve, as indicated. These bypasses act consecutively one after the other in consecutive stages of movement of the piston. In some circumstances, however, butone bypass may be used at the lower end of the cylinder 13.

When pneumatic poweris applied to open the door, the piston of said dashpot 13 will be in its uppermost position (number 1) and, as the pneumatic piston rises, the dashpot piston will descend but will move freely and at the desired high speed until the door, in its opening movement, approaches its full open position. At this time the descending dashpotpiston will reach approximately the position number 2 indicated in dotted lines and the liquid checking action, through the bypass 19, will act and continue to act until the piston reaches position number 3, when the bypass 19' will come into actionand the movement of the door will be completed under the checking action of bypass 19 At position number 3 bypass 19 ceases to act and the final movement of the door takes place under the checking action of 19 alone. During all of the downward movement of the piston for 13 the piston of 13 will rise but its relief valve will automatically avoid materially obstructing the freedom of movement of the parts under the action of the pneumatic power employed in opening the door and storing power in the spring for the closing movement. The checking action of the dashpot 13 in the closing movement may be regulated or determined by means of two or more bypasses 20, 20. These likewise are preferably arranged to operate at consecutive connected stages of movement of the piston downwardly and the checking action thus provided may extend throughout the whole downward movement or b suitable arran ment of the bypasses, may be made to come into action after the closing movement has proceeded to any desired extent. Also, it will be understood that under some circumstances the bypass 20 might be omitted and a r counterbore alone provided of the type illustrated. In any cases, however, the checking action must be such as to slow the movement of closing down to a speed which will be without danger of injury to persons passing through the opening. The opening movement, however, as described, is made much faster by adjustment of the bypass or bypasses so that the time consumed in the opening movement will be much less than that of the closing movement. In practice it may be made twice or more as rapid.

In the operation of the apparatus after the door has been opened and the power stored in the spring, as described, the valve is turned to allow the spring to act and close the door. The piston of 13 will then rise freely through the opening of its check valve aided, if need be, by the free flow provided by the counterbore. The piston of 13 will, in the meantime, descend, the first part ofthe movement when the two bypasses are employed being under the checking or retarding action of the bypass 20, which may properly be regulated to allow free and rapid action of the spring, so that the door may move rapidly in the beginning of its movement. As the piston of dashpot 13 reaches the lower portion of the cylinder the checking action produced by the presence of the regulable bypass 20 comes into play to prevent rebound or shock and allow the door to close gently.

In the opening movement it is obvious that considerable power must be applied pneumatically in order to store suflicientpower in the spring for the closing movement and at the same time to move the door quickly to open position. The danger of rebound or shock under this condition is effectually taken care of by the action of the dashpot 13. The checking action thus provided, it will be seen, is one appliedin stages independently regulable in each stage according to the requirements of the particular conditions under which the door is operated by the pneu-' matic power.

It would be, however, within my invention to employ a greater or less number of bypasses for each cylinder 13, 13' than is shown.

By the use of my invention the door may be moved rapidly both in the opening movement under the action of the applied power and in the closing movement by the action of the stored power and without danger of shock or rebound from a sudden application of pneumatic pressure sufiicient to store power, as well as with freedom from shock when the stored power is released to close the door. At the same time, by proper relative adjustment of the checking action applied respectively in the opening and closing movements as described, the total time consumed in-each door openingand closing movement may be greatly speeded up over that heretofore required, thereby greatly increasing the serv- 0. valve stem to a rod 21 operating,

ing of the same.

ice by diminishing the headway. The adjustability of the power of the spring aids in securing an eilective adjustment in conjunction with the regulable bypasses to produce a greater speed of movement of the door in opening than in closing.

The pneumatic valve may be actuated or controlled in any desired way, as for instance by coupling an actuating arm of the when raised by any suitable means, in a way to shift the control valve from the position shown in Fig. 4:, while the door is closed, to the position shown in Fig. 5 in order to effect the open- On the return of the actuating rod 21 to normal position, the position of the valve is reversed and assumes the position indicated in Fig. 4. So long as the rod 21 remains elevated, thus retaining the valve in the position indicated in Fig. 3, the door will remain open, being held by the pressure against the piston of cylinder 5 and against the tendency of the power stored in the spring 7. The actuating rod 21 may be guided in a fixed guide 22, as shown, and be provided with a spring 23 compressed between the collar on the rod and the guide 22 so that the rod and valve will be thrown back by said spring to normal position for closing the door automatically.

Said controlling or actuating rod 21 may be operated in any desired way, as for instance in the manner well known in the art by means of the bell crank lever 24 connected to the rod by one arm and adapted to be engaged, as to its other arm, by a pedal-operated cam 25 on the elevator car 30 adapted to be projected into position to engage said arm. Any other means could obviously be i used for actuating the rod 21 or the valve for each shaft door passed by the car as shown in the drawings or for the car door where the mechanism is employed on car doors without departing from my invention.

As will be seen, the retarding action of the one dashpot near the end of the movement of the door in one direction may be readily adjusted or regulated in the one or more stages of the last or final movement without interfering or disturbing the regulation of the action of the other dashpot by its bypass, which is effective in cushioning the movement of the door in the other direction. Also the extent and nature of the dashpot action at the difierent stages of movement may be readily determined in each case owing to the capacity for regulation at each stage independently of the other or others, thus permitting a complete control and smooth operation under all conditions or requirements.

It will also be seen that by the use of my invention the door may be made to close very slowly through its whole closing movement or it may be speeded up as desired at the beginning of such movement and checked or retarded at any desired rate as it approaches the closed position and at any desired difterent rates in the diiierent stages of such final movement.

It will also be obvious that by suitable regulation or adjustment of the respective dashpot actions the time consumed in the closing movement might be made less than that consumed in the opening movement under the application of the power. My invention,

however, is especially useful in speeding up the opening movement.

This application is a division of my United States patent application Serial No. 6509441, filed July 7, 1923, for pneumatic door operating mechanisms.

What I claim as my invention is:

1. In an elevator system, the combination with manually operable self-closing elevator shaft door operating means, of an elevator car and a motor driven power unit adapted to operate through said shaft door operating means to open said door.

2. In an elevator system in combination, a car, a door, manually operable toggle means for opening said door and for locking said door in closed position, spring means for closing said door and locking said toggle, and motor driven means adapted to act upon said toggle means to operate said door.

3. In combination with a movable elevator, a movable door, toggle mechanism operatively connected with said door for moving the same and locking it in closed position, spring means operatively connected to said toggle mechanism for closing said door, power means normally inoperative in the closed position of the door permitting said door to be moved independently of said power means, and means operable when the car is opposite a floor for operating said toggles and opening the door by said power.

Signed at New York in the county of New York and State of New York this 10th day of March, A. D. 1928.

CLIFFORD NORTON.

Ki i 

